Software and data security are important considerations for many companies and individuals. Typically, in order to help insure that a user at a computer is an authorized user, a user account is required to access the computer. As is well known, a user logs in to the computer using the user account by entering user identification information and a password. This type of system is effective so long as the user logs out of the computer when leaving it unattended. However, if a user leaves the computer terminal unattended, an unauthorized user may use the computer and access the software or data. This unauthorized user may misappropriate information from the computer. Accordingly, it would be advantageous to have a device which automatically disables access to sensitive software and data when an authorized user leaves a computer unattended. Furthermore, such a password system has the additional possibility of an unauthorized user misappropriating the password. In such a case, even if the authorized user has logged out of the computer, the unauthorized user may use the misappropriated password to gain access to the system. Thus, it would also be advantageous to provide a system which limits access to software and data to situations where the authorized user is in close proximity to the computer.
In addition to passwords being required to access a system, another method of limiting access to a computer is through a special piece of hardware or “dongle.” The dongle is a special piece of hardware that connects to the serial or parallel port of a computer. The software running on the computer sends a random number to the dongle. The dongle performs a secret computation and returns a result. The software makes a like computation and compares the results of the two computations. If the results match, the software continues to run. If the results do not match, the software does not run. Such a device is useful in helping to limit the misappropriation of passwords since the dongle is required to enable access to the software or data on a computer. However, similar to the situation described above where a user may leave a terminal unattended while logged in, a user may leave a terminal unattended with the dongle attached, thus opening up the possibility of unauthorized access. Thus, it would be advantageous for such a device to automatically disable when a user leaves a terminal while the dongle is attached.
Another method for limiting access to a computer is through card access to the computer. In such a system, the computer has an associated card reader, and user has a card which may be inserted into the card reader. The computer will not allow access to at least some data unless an authorized card is inserted into the card reader. The user typically wears the card around their neck, and in many cases are required to wear the card around their neck. Accordingly, when the user leaves the immediate vicinity of the computer, they must remove the card from the card reader, thus disabling access to restricted data through the computer. While such a system is effective in limiting access to restricted data, it can be very inconvenient for a user. The user must place the card into the reader, which requires removing it from around their neck, which may result in the user inadvertently leaving the card in the reader. In some cases, the user may have some type of retractable cable which connects to the card, and thus does not need to remove the card their person. However, when working at a computer it can be uncomfortable and inconvenient to have a card extending from the user to the computer. Accordingly, it would be advantageous to have a device which automatically disables access to restricted data when a user leaves a terminal which does not require the user to perform physical steps to enable and disable access.
Further adding to the possibility of unauthorized access is the increasing reliance on mobile devices such as laptop computers. These devices may be used in areas away from relatively secure areas of an individual's home or a company's building. When such a device is used in areas which are relatively insecure, such as an airport or a train, the number of potential unauthorized users increases, thus increasing the possibility that an unauthorized user will use the mobile device to access the software and data. Furthermore, such mobile devices are much more susceptible to theft. Thus, even if used in a relatively secure area, the device may be stolen and removed to another location relatively easily. If a dongle is used with the device, the dongle may also be taken if left attached to the device. This further increases the potential for unauthorized users to access the system. Accordingly, it would be advantageous to insure that a mobile device is secure, and that data and software stored on the device are less susceptible to access by unauthorized users. Furthermore, as mentioned above, it would be advantageous to have such a system which would automatically place the computer in a more secure state when an unauthorized user is not within a certain distance from the computer. Such a system would help insure that the data and software located on the computer are not accessible by an unauthorized user.